The present invention relates to novel acetyl transferases, nucleic acid sequences coding therefore, expression constructs and vectors comprising these sequences, microorganisms transformed therewith and processes for the microbiological production of carotenoids, as for zeaxanthin, astaxanthin, lutein or β-cryptoxanthin.
Carotenoids are organic pigments ranging in color from yellow to red that are naturally produced by certain organisms, including photosynthetic organisms (e.g., plants, algae, cyanobacteria), and some fungi.
Carotenoids such as lutein, zeaxanthin or astaxanthin are important additives in the human and livestock diet as pigmenting substances and precursors of vitamin A derivatives. In addition, carotenoids have a health-promoting action such as enhancing the immune response and, by reason of their antioxidant properties, a cancer-preventing action, which makes their use as nutraceuticals of interest. An economic process for preparing carotenoids and foodstuffs with an increased carotenoid content is therefore of great importance. Particularly economic processes for preparing carotenoids are biotechnological processes which make use of proteins and biosynthesis genes of carotenoid biosynthesis from carotenoid-producing organisms.